


Amok Time Lord

by tiliquain



Series: The Amok Time Lord Series [1]
Category: Doctor Who (2005), Star Trek: The Original Series
Genre: Alien Sex, Alternate Universe, Animal Transformation, Anthropomorphic, Frottage, M/M, Oral Sex, Pon Farr
Language: English
Status: Completed
Published: 2012-05-15
Updated: 2012-05-14
Packaged: 2017-11-05 09:51:07
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 15,200
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/405070
Author URL: https://archiveofourown.org/users/tiliquain/pseuds/tiliquain
Summary: <blockquote class="userstuff">
              <p>The Doctor and Jack Harkness find themselves in another universe, and experience some strange effects from a Vulcan mind-meld.</p>
            </blockquote>





	1. Chapter 1

*****

Introduction

*****

First, some backstory. I'm very new to the Doctor Who fandom. I started out in the Star Trek fandom, and drifted into the furry fandom, since my husband's more into furry art... that's most of what I do these days, since (1) it's something we can share together, and (2) I can actually make money drawing furry stuff. But before I met him, I wrote Star Trek fanfiction-- mostly erotica about Kirk and Spock as lovers. And, sexually speaking, I'm still more of a Trekkie than a furry. 

I love drawing furry art, but when it comes to getting myself turned on, I always seem to come back to Star Trek. Specifically, Vulcans. I've had the hots for Spock since I was 13. That's been-- god, almost 20 years. And in that time, I've gone through every fantasy I could possibly put him in. Spock will never stop being sexy, but for me, his sex appeal has worn out just enough that I'm starting to consider other science fiction characters to fantasize about.

So when one of my furry friends introduced me to Doctor Who, my fantasy life latched onto the Tenth Doctor and wouldn't let him go. But, as always, my Star Trek fetish insisted on getting involved.

When I have sexual fantasies about people-- even people who are as un-Vulcan as you can get-- I always end up imagining them in pon farr. That's the Vulcan mating season, as described in the Original Series episode "Amok Time" and a few other points in the show. When that time rolls around, normally logical Vulcans go insane with sex drive, and have to mate in order to stay alive. To me, it's one of the hottest things ever. Yes, I know, I'm a pervert-- but I'm a happy one.

So, here's "Amok Time Lord"-- my furry/Star Trek/Doctor Who crossover story. It has Spock and Kirk and the tenth Doctor and Captain Jack Harkness, and weird alien genitals, and transformation and pon farr, and cat people from both the Star Trek universe and the Doctor Who universe. (I just had to have cat people-- they're the only furries that exist in both Star Trek and Doctor Who! Except, the ones in Star Trek are only in the Animated Series, which no one watches-- but whatever.)

For Spock, the story takes place during the episode "Amok Time." For the Doctor, it takes place just after "The Waters of Mars." The Doctor and Spock clearly live in different universes. In the episode that first introduces Jack Harkness, the Doctor and Rose actually mention Star Trek a little-- in their universe, like ours, it's just a TV show. But in this story the two universes collide.

I have years of experience with sex stories about Spock, but when I wrote this, I'd never read any Doctor Who fanfiction at all. I don't know what the cliches are. I don't know if there's any fan consensus on what a Time Lord's naughty bits look like. I made it all up, in my head one morning as I was lying in bed fantasizing. And then I told my mate about it, and he convinced me to make it into a story.

 

*****

Amok Time Lord

*****

 

"How do you figure it, Chekov?" Sulu leaned over from the helm, a long-suffering smile on his face. "First we're headed to Altair. Then we're headed to Vulcan. And now we're headed back to Altair."

Chekov rolled his eyes. "I think I'm going to get space-sick."

There was a quiet moment on the bridge, neither crewman feeling sure how to react to the strange series of orders. Something was going on with the half-Vulcan first officer, that much was certain-- something so important that the captain didn't seem to know whether to set course for Mr. Spock's home planet or the inauguration they were scheduled to attend on Altair Six. But only Captain Kirk knew exactly what the deal was, and maybe even he didn't know for sure. Spock was a closed book sometimes, even to his best friends.

"It's got something to do with Mr. Spock, I know that," Sulu said, leaning toward Chekov again. "He's been acting strange. Everyone says so."

"You're telling me." Chekov's voice lowered a decibel. "I saw him walking to his quarters last night, and--" the last words were almost a whisper-- "he had a hard-on."

Sulu made a noise that was half-gasp, half-laugh, drawing a curious glance from some of their crewmates. "Pavel, what do you think this is, high school?" he whispered back. "You can't say that sort of thing on the bridge!" As he regained composure, though, his eyebrows went up. "Seriously, though? Mr. Spock? Well... he's a guy too, I guess. It happens to all of us."

"I am betting you, it's been a long time since he got laid," Chekov muttered. "If he's acting crazy, I am betting you it is because of that. It's not good to keep that bottled up. As one of my Russian ancestors said... if there is a gun, it has to be fired... or something like that."

 

*****

 

The TARDIS floated in orbit around Mars. The door was open, the Doctor staring out through the protective forcefield around it. Below, on the planet's surface, the explosion of the base went on, unstoppable. The burning cast reddish light across his face, even at this distance.

He had rescued the base's commander and brought her back to Earth, only to bear witness to her suicide. And no matter how many times he traveled back to this moment, he would never be able to stop the explosion, would never be able to save everyone. It was destined, a fixed point in time. He had come back this time just to look at it, for a few minutes, before he moved on. It seemed he was morbidly fascinated at both the event itself and the unnatural compulsion he had acted on, trying to interfere in something destined and fixed.

And then, above him in the sky, he saw something completely undestined and unfixed. "What?" he blurted, craning his neck, his mouth hanging open.

It was a small spacecraft, not of Earth origin, not of any origin the Doctor recognized-- burnt and torn apart, hurtling toward the Martian atmosphere. Streaks of fire trailed after its small roundish body, as it vented and burned its own air supply. The Doctor staggered back a few steps as he stared up at it, watching it fill more and more of his field of vision every millisecond.

It was, in fact, on a course that would pass uncomfortably close to the TARDIS. He was giving serious thought to moving out of the way, when he noticed that the door of that spacecraft was open too. A silhouette was standing in it, barely visible at its great speed-- a humanoid figure, waving both arms at him.

He didn't have much more time to think before the small ship was whooshing past him, and the man was leaping out across the space between them to land inside the TARDIS-- face down, on the floor, on top of him, knocking him onto his back.

"What?!" said the Doctor again, before blinking and focusing his eyes on the face of Captain Jack Harkness.

 

*****

 

Jack tried to slow his breathing, as his mind adjusted to being free from his crashing shuttle and inside the TARDIS. He hadn't meant to land in this position-- god, a sexy Time Lord body underneath him was a distraction he could do without, right now, pleasurable as it was. "Sorry," he muttered, trying to get up, but still too shaky with the adrenaline from those last few moments when he'd thought he was going to burn up in the atmosphere, along with the shuttle.

Of course, probably even that couldn't have killed him. All too easily he could picture himself stepping unscathed from the dust and molten metal of a crashed ship's remains. There was no way to know if he was completely immortal; he only knew what hadn't killed him so far. But ever since that bizarre resurrection after Rose had looked into the heart of the TARDIS, there were a shitload of things that hadn't been able to kill him. 

And, god, it felt good to be here. Forget the eye-candy of being able to look at the Doctor again, forget the feeling of that hot lean body under his own-- really, try and forget it, Jack thought to himself; don't focus on what you can't have-- but just being in the presence of that brilliant mind made him feel safer already. 

It had been a long few weeks, being tied up in chairs and strapped down on tables and locked up in cells, with that lunatic geneticist stepping in every few hours to inject him with things and take tissue samples. The thought of his invulnerability hadn't been much comfort throughout that time-- an endless life wasn't much fun if you spent it imprisoned. 

But if there was anyone who could just plain laugh in ridicule at an enemy who tried to keep someone locked up, it was the Doctor. Gratitude and affection warmed Jack's whole body, and again he tried to get up, hoping the warm feelings wouldn't turn into more noticeable physical reactions. The Doctor felt way too good underneath him, and it had been too long since Jack had had sex. As soon as the Doctor got him somewhere safe, he'd have to find someone and get laid right away. 

As soon as he got somewhere safe. The warm feeling grew. He knew he was going to be safe now, just because of who he was with. No matter what happened, the Doctor would help him find a way to fix this whole crazy mess. He always did.

 

*****

 

The Doctor was still staring up at Jack, nothing in his mind but bafflement. Finally he managed to get his bearings, and wriggled backwards, scooting out from under the human. "For God's sake, Jack, what's going on?"

"Not even a hello, huh?" Jack gave a rueful smile. "What's going on? Well, I'm running. The guy chasing me-- he's way too good at finding me. He's found me a bunch of times already, and last time he got in a few fatal shots before I managed to warp my shuttle here. I use the phrase 'my shuttle' a bit loosely, mind you, since I stole it from him." The captain's mouth twisted up on one side, and he sat up, one leg outstretched in front of him, one bent at the knee with his arm resting on it. "So what's been going on with you?"

The Doctor started to stand up. "Oh, I've had plenty of things happening in my life. Thanks so much for adding to the excitement; I've now got more fun than I know what to do with." He kept staring at Jack. The human was wearing his usual outfit, the suspenders and the long black coat, and there was a worn-looking knapsack on his back, probably containing whatever basic necessities he'd been running with. "Is that why he was chasing you? Because you stole his shuttle?"

"No, he's chasing me because he wants to do genetic experiments on me." Jack stood up, took off his knapsack and set it on the floor. Meanwhile his eyes were giving the Doctor's body a once-over, slowly trailing up from his legs to his face, making lengthy pauses at various points in between.

The Time Lord turned away, his face heating. It was scandalous, how blatant Jack was when he felt attraction. No wonder he appealed so much to every adventurous human he met. Hell, if the Doctor had been a human, he could even imagine himself responding. 

But-- his face burned hotter, and he shook his head to get the thoughts out. He wasn't a human; he was a Time Lord on his tenth life, and that life was about to end. Even the thought of intimacy tasted like ashes now. "Well," he muttered, still not looking at Jack fully. "So what do you want me to do about it?"

"I'm not sure." Jack shrugged. "His ship has equipment that can gene-scan a whole planet and find a specific person, so hiding from him isn't easy. Maybe I'll be able to manage it now that he doesn't have the shuttle to scan for as well. I was hoping you might have some ideas."

"Well," the Doctor said, leaning against the central console of the TARDIS. "Well. I don't suppose he can time-travel, can he?"

"I like the way you think!" Jack grinned and pointed a finger at him. "No, I'm pretty sure he can't. And I'm even more sure that he couldn't figure out what time we'd gone to, once we'd made the jump."

"Well, all right then." The Doctor could still feel Jack looking at him, making his skin burn with self-consciousness. "I suppose we'll be off, then. Where and when would you like to go? Any preferences?"

But just then, an alarm erupted from the console, and one screen flashed with a red-lettered warning. The Doctor gripped the monitor on both its sides, staring at the readout. "What? Unidentified craft approaching?"

"Oh, shit, hurry up before it's too late." Jack rushed to the Doctor's side, looking at the console as if wishing he could set the coordinates himself.

The Doctor's eyes darted toward him-- then he did a double take, staring at Jack's face more closely. 

If it was still Jack's face. The Time Lord's mouth hung open. "My God! What happened to you?"

In the last minute, the human eyes had brightened to an impossible shade of green, with vertical slits for pupils. The indentation above the upper lip had deepened until it formed a distinct line from nose to mouth. And the nose itself had taken on the appearance of a downward-pointing pink triangle. Otherwise, the features were the same, but the change was jarring to say the least.

Jack gave a grimace that showed unusually small front teeth and unusually long canines. "It's a long story. And I apologize if I'm wrong, but I'm guessing you're not really interested in a long story right now, since there's probably a crazed geneticist outside with a universal transporter aimed at your ship."

"A what?!" The Doctor leapt to his feet, then fell back down, because at that moment the TARDIS shuddered as if time and space themselves were ripping apart around it. The heaving of the great machine tossed them both across the floor like toys, grabbing hold of anything they could. 

When the chaos died down, Jack found his way to the wall by the door and sat up, leaning back against it. "That would be the universal transporter," he said. 

The Doctor scrambled back to his feet and ran from side to side of the console, pressing switches and glaring at displays. When he realized what had happened, a wave of panic ran through him.

"They can't do that!" he shouted, grabbing one small monitor with both hands. "What, do people think they can just walk into a shop and buy a new time-space continuum after they've wrecked this one? You can't just go round sending people into other universes! It--"

"--Tears the fabric of time and space. I know." Jack folded his arms. "And yet he did it."

"Who's he? Never mind, I don't want to know right now." The Doctor threw a switch that didn't seem to help much, because the TARDIS responded by rocking and pitching like a ship in a storm. "Hell, I can't even get us to materialize properly. Let me--"

"He's a geneticist," the captain replied to the withdrawn question. "Name of M'Rai. He calls himself a Caitian."

The Doctor hung on to a lever until the rocking quieted somewhat. "A what? Is that a species?"

"I guess so. You haven't heard of it?"

"Never. What did he look like?"

Jack gestured to his own transmogrified eyes and nose. "Like this, only more so. At least when his perception filter was off." 

The floor began to vibrate, and Jack lay down on his side, seeming to decide that sitting upright wasn't worth the effort. "He got involved with some scientists on Earth, who seemed to be taking some of the first steps toward genetically altering humans. He kept trying to influence them. The guy's pretty insane, Doctor. His one goal in life seems to be convincing everyone in the universe to alter themselves to look like him. Not just this universe, either, but every universe."

The vibration grew to something like an earthquake, and the two of them hung on to furniture and pillars for dear life. "Okay," the Doctor shouted. "All right, I can see why he took an interest in doing experiments on you-- probably thought you'd be a fascinating genetic subject, what with your inability to die and all. Totally wrong, of course, since that's got nothing to do with your genes, but he couldn't have known that. And given his mentality, I can understand the way he changed your appearance, though I would have expected him to go further with it. Still, what I don't understand is--"

"I think he did mean to go further with it," Jack called out, rolling across the floor. "And I think he succeeded. It's just that with some of his subjects, it's a slow transition." He landed in a corner. "It's been starting over the last minute or so. My nose was the first thing to change. Second was a part you can't see right now--"

The Doctor rubbed his head with the heel of his hand as the quake began to subside. "I'm terribly sorry, Jack, but now is not the time to start having a chat about your feline genitalia."

The sharp teeth showed in another grin. "Are you sure? They're really interesting. I'd even let you touch them."

"I'm sure." The Doctor's hands seized another lever, and the tremor of the floor was replaced with another bout of rocking motion. Was Jack's inexplicable transformation actually making him more lewd? God, this was as distracting as all hell. "I'm sure they're fascinating. I'm sure it's marvelously huge, and I'm sure my scrawny arse is far too small for you."

Jack's cat eyes glinted. "I bet it's bigger on the inside."

Blushing heat made the Doctor's face burn. "Oh, like I haven't heard that one before."

"You have? Really?" Jack's forehead wrinkled, though the motion didn't seem to work so well now that his face had changed. To the Doctor, it seemed that he'd become even more catlike in the last few seconds: his hairline had lowered, his forehead was broader and his chin smaller, and the bridge of his nose had become narrower and more defined, like two graceful lines coming down from the inner corners of his eyes. It actually looked rather sexy on him-- 

The Doctor shrugged, a vigorous motion like trying to shake something off his shoulders, as he struggled not to let himself think about anything except materializing the TARDIS. "I meet a lot of people. I've heard everything."

The captain lay down on his stomach, resting his chin on his hand-- was it a hand, the Time Lord wondered, or a paw? Well, it still had opposable digits, so he was going to think of it as a hand, even if it was growing claws and fur and paw-pads. The pads looked so soft-- 

Bloody hell, stop thinking things like that! Was he obsessing on Jack's sex appeal just because it made him feel alive, now that he was about to die any day? Well, it was no use; getting turned on by a human wasn't going to save his life. Death was still going to knock four times and then take him.

"Besides," Jack went on, "I never said I wanted your ass anyway. There are so many different acts of love to choose from..." The voice sounded far too seductive, as if even Jack's vocal cords were transforming so they could purr.

The rocking of the floor intensified. "I'm sure there are," said the Doctor, turning a knob with one hand and scrolling through a readout on a screen with the other, while trying to stay on his feet. "But right now, I can't really focus on that, because I'm trying to--"

The rocking slowed, and for the first time in ten minutes, the floor seemed solid.

"--Land the TARDIS," he finished.

 

*****

 

The floor hadn't shaken for five minutes now.

"So," Captain Jack Harkness said, getting to his feet. "You-- materialized us?"

"Yes. Yes, I did." The Doctor ran a hand through his hair, feeling a headache coming on. "That bumpy ride was a trip into another universe, all right-- but the trouble is, I've got no idea what universe, or where in it, or how to get back. The question I was about to ask, when you interrupted me to talk about your naughty bits, was-- have you got any idea why, exactly, M'Rai the mad Caitian geneticist decided to send the two of us to another universe?"

Jack shrugged. "If I had to guess, I'd say it's his universe." 

The Doctor felt his eyebrows draw together. "His universe? And why would you guess that?"

"Because he told me." 

"Ah."

"Basically," Jack continued, "he hunted me down, tied me up, experimented on me, injected me with the-- the cat stuff-- and then he told me he was from another universe, and he was going to take me back there to keep me as his own personal research subject, or something." He rubbed the side of his face. The fur was all around his jaw and chin by now, sleek tabby-patterned fur, leaving only a small hairless patch around his nose. "I escaped, stole a shuttle, and ran. He chased me. He was still chasing me when I found you. I suppose he dragged you along into this universe just because you happened to be in the same box as me."

The Doctor made a face. "No, you happened to be in the same box as me. It's my box." His eyes burned as he glared at Jack. "Why the hell did you have to get me involved in your problems? I've got problems of my own, you know." The thought of the prophecy tingled in the back of his mind, the four knocks that would signal his death, probably very soon. Jack didn't know the half of it, really. God, the Doctor really didn't need anything more to fuck up his life right now. But nobody ever asked him before they dumped more trouble in his lap. 

Jack stared at the floor. "If I hadn't found you, he would still have brought me back to his universe. And I don't know if I could have gotten back on my own. And-- and you said it yourself-- he's ripped a hole in space-time. You're the only person I know who can fix one of those."

"Well." The Doctor put on his spectacles, starting to walk toward the door. "Well, in any case, he's probably in this same universe, then, trying to find us. Maybe he's close, and maybe he isn't. Maybe the rift he tore in space is nearby, and maybe it isn't. But I suppose the first step would be to look outside and get some idea of where we are."

 

*****

 

The door of the TARDIS opened into a bare hallway, lined with the doors of rooms. The two of them stepped out and began to walk down the hall.

"Where are we, a hospital or something?" said Jack, scratching his face again and wincing. The claws had just finished forming on his hands, and the ear he'd scratched had become very thin and sensitive, stretching into a point and moving up toward the top of his head. He folded his clawed hands behind his back, and fixed his eyes on the attractive rear view of the Time Lord walking ahead of him.

The Doctor was looking around, head forward and mouth slightly open, as if listening for faint sounds and vibrations. "No. No-- it feels like a starship."

The mention of a starship triggered something in the captain's memory-- something from his years of being saturated in twentieth and twenty-first-century culture. Seeing his surroundings in that light, they began to look familiar. But it was impossible...

"So... there are parallel universes for everything, right?" he asked. "Every possibility."

"Oh, oh yes," the Doctor answered, attention still focused on the doors as they traversed the corridor. "Everything that could have happened. Everything you can imagine that can't happen. Everything you can't imagine."

"So, if someone in our universe made up a work of fiction-- like, say, a television show--" Jack began, "even if things happened in that show that would break the laws of physics in our universe-- there's still going to be a universe, somewhere out there, where all those same things actually happen?"

"Of course." The Doctor looked sideways at him. "Why do you ask?"

Captain Jack shook his head. "Just curious."

They had reached a door that seemed to interest the Doctor very much. He stared at it intently for a second, that wide-eyed insane curious look on his face, adorable and sexy at once-- then he grimaced, stumbled backwards, and pressed his hands against the sides of his head.

"Doctor? What's wrong?" Jack rested a hand on the Doctor's shoulder, concern flooding through him. The Time Lord's teeth were showing as if he were in pain, and Jack's hand only seemed to make it worse. The sight of him hurting made Jack hurt too-- god, he cared way too much about this crazy alien. "Doctor, talk to me. Are you okay?"

Then as he felt fabric give beneath his fingertips, Jack pulled his hand away, realizing he didn't yet have full control over his claws. They were long and sharp, and fur had spread across most of the skin of his hands by now. "Sorry. But what happened?"

As Jack let go, the Doctor staggered back until he collided with the opposite wall. "There-- is an insanely intense telepathic energy, emanating from in there," he said, his eyes still clenched shut, his hands fumbling to take off his spectacles and put them away. 

"From what?" Jack felt that urge to comfort him again, but his clawed hands weren't going to help matters.

The pain finally seemed to have faded; the Doctor was opening his eyes to stare at the door again, that lovable look of curiosity sneaking back onto his face. "If I had to guess, I'd say there's a powerful telepathic being inside that room, going through some extreme emotional and physical stress of some kind." 

The captain's own eyes focused on the door too, his apprehension building despite his own curiosity. "And you want to go in and see what it is, don't you?"

"Oh, definitely," the Doctor said, reaching into his pocket for his sonic screwdriver.

 

*****

 

Spock huddled in a corner of his quarters, trying to meditate.

He had just gotten Nurse Christine Chapel to leave, asking her to make him another bowl of soup, placating her gentle concern for him by giving her something to do, so she could feel as if she was helping. 

But nothing she could do would really help. If she made him soup, he would probably not be able to eat it. His appetite had faded days ago, all his energy focused on one single physical urge. He clasped his hands together in meditation, doubling over, feeling the heat and hardness of his erection strain inside his clothes.

If Nurse Chapel hadn't left, he might have lost control and tried to burn out his sexual firestorm with her body. She would probably have been willing-- but it wouldn't have helped; it wouldn't have sated him. He was drawn in a telepathic tractor beam toward his own planet, the madness of pon farr refusing to release him until he came home and took the mate his family had chosen for him.

If it had been his own choice, the pon farr would be drawing him to another cabin on this ship. Even now, the fantasies of home were tangled up with fantasies of his captain, Jim Kirk-- the mischievous human smile, the soft human flesh against his own. He moaned and shook his head-- there was no logic in such a desire. It was un-Vulcan in every way. He was a shame to his father's species; his human blood made him a scandal to his planet.

His planet... the pon-farr-induced longing for home took over. Nurse Chapel had helped in one way. She had informed him that the ship was finally on course for Vulcan again, that he would be home in a few days. Perhaps he would get there in time, before the mating drive tore him apart, before he went mad and died. 

The door of his quarters opened, without a knock or a press of the buzzer. He felt the presence of other beings in the room after the door slid shut again, but he was far gone now, caring about nothing but the blood fever inside his own body. 

"Are you all right?" a voice called out. 

 

*****

 

The Doctor blinked in the low, reddish light, making a face at the crimson curtains and the statues in the shrine. "Quite the melodramatic decorating job," he murmured to Jack, but he suspected Jack didn't care. The human's eyes were focused only on him-- he didn't know if it was concern, or lust, or a mix of both, and he didn't want to know. He didn't want to think about what Jack felt for him. They were feelings that weren't going to do either of them any good, and thinking about them too much made the Doctor's own emotions start to feel tender enough to hurt. So he packed them away in the back of his mind again, and tried to focus on the immediate situation.

"Are you all right?" he called out again at the crouched figure in the corner. When there was no reply, he approached the man and knelt down beside him. The telepathic energy was thick in the air-- it felt as if the poor fellow was going quite insane.

The Doctor peered closely at what he could see of him. The man was dressed in a blue shirt and black trousers, his body curled up almost in a ball, his face turned down. But his head was visible-- short black hair, and elegant pointed ears.

"Well, this is interesting," the Doctor murmured. The only reply was continued heavy breathing. 

"Can you hear me? I might be able to help you." Cautiously he reached out his hands, settling them against the sides of the tense face... opening his mind to telepathic communication, focusing on creating mental shields that could protect his own mind while letting him gather knowledge about the madman's condition. 

His fingers met hot damp skin, and it was like completing an electrical circuit. No, it was like touching a sun. Waves and waves of smoldering heat rushed in on him, crushing his shields like paper, explosions of emotion and physical sensation going off in every centimeter of his body, knocking him back onto the floor. 

He sat there stunned, clutching his head, as dizzy and confused as if he'd just regenerated. Heat and light and madness were still roiling throughout him, burning his skin and offsetting his sense of balance, accelerating his heartbeats to a near-painful pace, blinding his mind's eye with white fire... he didn't know where to start sorting it all out...

"Doctor!" Jack was kneeling beside him, but he was just a blotch of darkness in the corner of the Doctor's eye, a warm presence beside him that didn't seem to mean anything just yet. The man in the corner was getting up, clearer than Jack in the Doctor's vision, advancing toward the two of them with insanity burning in his eyes. 

 

*****

 

Jack stared at the madman's face. The pointed ears, the fringe of black hair, the slanted eyebrows-- he blinked with a sense of recognition, but mostly disbelief. "God, it really is true," he murmured, "what you said about universes."

He finally managed to lift the dazed Doctor to his feet, being as careful as he could with his claws, and the two of them staggered toward the door with their arms over each other's shoulders. But the Vulcan was too fast, seizing the Doctor from his grasp and pinning him against the door, strong hands on his biceps.

What happened next shocked Jack to the core of his being. Spock pressed his entire body against the Doctor's, his legs spread and his knees against the door on either side of the Doctor's legs-- and kissed him. 

It was an animalistic kiss, like an attempt to devour him, hands woven through the Doctor's hair and clutching his head tightly as the madman's mouth explored and invaded his, for long moments, making occasional detours to breathe against his neck and bite at the skin below his ears. It was enough to make Jack shiver with a combination of panic and arousal-- and those feelings doubled and tripled when he saw that the Doctor was actually responding. 

The Time Lord's neck arched back, a moan coming from his throat as he let Spock's mouth follow his movement, pressing his head against the door with the force of the kiss. His expressive face was flushing, his eyes closed tight under lowered eyebrows, and his hands were making their way to the Vulcan's backside, pulling their groins closer together. Both men started bucking against each other through their clothes, as their mouths met, as the kiss became utterly mutual. The Doctor was pressing his mouth back, opening to the Vulcan tongue, and when Spock moved to explore his neck and ear, he gave a gasp and moan that brought Jack's newly feline cock to full erection in a matter of seconds. 

But no matter how sexy he found this situation, Captain Jack couldn't ignore the fact that it might be dangerous. The Doctor was under the influence of a powerful telepathic mind, and it was clearly altering his thought patterns, changing his motivations. It could be damaging the Doctor's mind every moment that the contact continued. "Ssstop it," he called out, stumbling on the words-- his tongue had begun to change in shape and texture, and the unaccustomed roughness made speech difficult. 

So he turned to actions instead of words, seizing the Vulcan from behind, his clawed hands gripping the hot and muscled arms and trying to pull him away. But Spock was too strong, and his motivation was too powerful. He shook off the attempt to tackle him as if it were an insect landing on his back.

Jack ran his transforming tongue over his teeth. He would have to speak Spock's language, then. 

He approached the rutting alien from behind again, but this time, instead of behaving like an assailant, he embraced him, kissing the back of his neck roughly with his sharp teeth and sandpaper tongue, pressing his still-hard cock against Spock's tight backside. It was almost enough to drive Jack himself beyond control, the alien heat and copper taste of the Vulcan neck, the pressure of that taut ass when his erection was craving touch more than anything...

The feverish body gave a shudder, and released the Doctor to turn around and face Jack. Spock's eyes were on fire, his lips flushed and swollen, his breath heaving. He was fucking gorgeous. Jack's eyes darted to the side, seeing the Doctor slump with his back against the door and stare at the two of them as he struggled to stay upright.

Jack's urge to get the Doctor to safety clashed for a moment against a new urge he felt as he looked into those fevered eyes. He didn't think Spock was influencing him telepathically-- he wasn't a telepath himself, and he hadn't been the one who tried to mind-meld with the guy-- but there was certainly an influence of some kind happening here. 

Their two bodies turned, circling each other, Spock finally getting Jack cornered against the door where he'd had the Doctor. Jack glanced to the side, seeing the Doctor still leaning there, looking confused and scared and something more. 

He turned his eyes back to Spock, but while he let the madman's gaze feast on him, his hand was creeping toward his friend's waist. 

His fingers brushed the Doctor's groin first, by mistake, feeling a warm firmness that lingered in his tactile memory long after his hand had passed it. The sensation of it, and the responsive motion of hips that followed, actually made Jack gasp softly-- and the moan he heard in response made his breath catch. But he kept moving his hand, across the thrusting hips until he found the pocket with the sonic screwdriver inside it.

It seemed this door was supposed to open on some electronic command he didn't know about, but he could probably get it open with the screwdriver. He hadn't used the thing before, but he had experience with various sonic devices of his own, left over from the future, his past. He could probably figure it out. If he could keep Spock distracted. With the hand that wasn't invading the Doctor's pocket, he grasped the back of the Vulcan's head and pulled him close. 

Thank god his lips were still human enough for kissing. Spock didn't seem to mind the pain of the sharp teeth and rough tongue at all-- he put his whole Vulcan strength into kissing back, growling in his throat. As he started to press the superheated bulge in his groin against Jack's leg, the captain's other hand managed to push the right button as he held the sonic screwdriver against the lock-- finally making the door slide open.

With all their weight leaning on the door, the three men were thrown off balance by its motion. Jack, not being insane, recovered first. Pushing the Doctor out into the hallway, he pulled the door shut on Spock and hit it with a pulse from the sonic screwdriver, hoping that would keep it closed long enough for them to escape to the TARDIS.

"Doctor?" He pulled the disoriented Time Lord to his feet and draped the unresponsive left arm over his shoulder. The Doctor was conscious, but not fully aware-- his face was flushed, his breathing was hard and irregular, and Jack had to do most of the work as they ran down the hall the way they'd come. 

Hearing the Vulcan beating at the inside of his own door, Jack glanced back for a second. It was too bad, really. He'd been curious what Spock looked like naked.

*****

To be continued

*****


	2. Amok Time Lord: Chapter 2

**Summary for the Chapter:**

> The effects of the mind-meld become clear, and things get a bit complicated.

*****

Safely inside the TARDIS, Jack laid the Doctor down on the floor and bent over him. The Time Lord's eyes were wide open, and as fiery-looking as Spock's. He was still breathing hard. Jack could feel the heat radiating from his body through his rumpled suit. His hair was disheveled, his face shining with sweat. 

"Doctor, talk to me," Jack said, patting at the side of his face, his heart hammering at the thought that the Doctor's mind might be seriously damaged. "Are you okay? What's happening? What did he do to you? --Besides the obvious, I mean."

The Doctor's breath came faster, and he leaned his face closer against Jack's feline hand. The touch made Jack blush under his fur. "I-- I don't know," the Doctor said, rubbing his face on Jack's paw pads as if craving the contact. "I think I'm dying."

"You're not dying," Jack said, even though his heart kicked up a notch at the thought, starting to panic at the possibility that it might be true. "Why do you think that?"

"Well, I-- I don't know what's going on," the Doctor gasped, stretching his neck to the side. "It's some kind of mental overload-- something c-controlling my mind, making my brain set off too many physical reactions at once. I d-don't know what it is. But I know if it keeps up, it'll kill me. I can feel that much."

"So you're... going to regenerate?" Jack hated it, hated the thought of losing this gorgeous body, and losing whatever parts of the Doctor's personality would be lost in the next regenerative cycle. But, God, it would be better than losing all of him.

"Well, I would regenerate, except it's-- it's the sort of death where you go mad before you die." The Doctor's eyes clenched shut and his teeth showed in a grimace as he twisted back and forth, enduring whatever telepathic agonies the mind-meld had spilled inside his head. "I can't-- think clearly enough to start the regeneration-- the madness has already got the part of my mind that would take care of that. I'm--I'm just too distracted."

Jack leaned close. "What's distracting you?" he whispered, his breath on the Doctor's face. "What is your mind trying to focus on instead?" 

His skin burned with adrenaline as he considered the possible answer. Spock's mind had been pretty damn certain what it wanted to focus on. It had looked like a madness with a specific goal-- one that, if achieved, might successfully resolve the condition. And if that same madness was what had passed into the Doctor...

The response to his question was volcanic. With a throat-deep groan, the body on the floor lunged up at him, the hands seizing the collar of his shirt and pulling his face against the panting mouth beneath him. 

It was more than a kiss, it was a bruising pressure that drove his teeth against the Doctor's lips, and it didn't stop with the pain or the taste of blood. It went on and on, the Time Lord's hands moving from his throat to entangle in his hair, clutching his head as if keeping him there was the key to survival itself-- which it very well might be.

And then it eased just slightly, his continued presence calming the Doctor's panic, and became passionate and not just desperate. The hands massaged the back of his head, where the hair was still thick and black, and the Doctor's mobile mouth opened and closed and moved against his-- still pressing hard, still urgent, but now hot and wet with pleasure, the pain starting to fade. 

Jack moved until he was straddling the body below him, not breaking the kiss but adding more contact. As their bodies pressed together, the Doctor moaned so hard his mouth broke free for a second, and as their lips came back together the Doctor's hands started to move from his head and neck down the wide muscles of his back.

The urgency, the need in that embrace-- it brought on a flood of pleasure, threatening to spill the madness from one mind to another. Jack let himself respond completely, stroking his rough tongue against the Doctor's smooth one, tasting his mouth, wrapping his arms around the Doctor's back, arching his own back and pushing his hips down. 

The sensitive bulge of his groin pressed against another that felt even firmer, and three times as hot, and seemed to be moving in ways nothing on a human's body would move. The moan that answered his thrust, and the frenzy of bucking that almost threw him off as soon as the contact happened-- it drove him insane with the urge to tear away the clothes, caress that slender and desperate body in every way he could think of. The Doctor looked sexy as all hell, his hair in a mess, his eyes half-closed with the pupils dilated wide, a hot blush creeping up his cheeks as he paused to take deep fast breaths between kisses.

But at the same time, Jack was realizing he had no idea what he was getting into, no idea what was involved in making love to a Time Lord. What exactly was he rubbing his crotch against-- that alien heat and inhuman motion of flesh? What would happen, with the Doctor raving mad on some alien mating urge, unable to go slow or be gentle?

Jack slowed his breathing, trying to stay calm. He couldn't be permanently injured. He was the only human who could be sure of being totally safe in this situation, so he was just going to have to let the fear go, and give in to the pleasure.

He leaned in for one more long deep kiss, both men's hands grabbing and clutching at each other's backs with each shift in position, as if they couldn't find a way to hold each other tight enough to be satisfied. At one point Jack gripped the Doctor's waist so hard that he felt his claws tear fabric, and he was pretty sure he broke the skin before he managed to stop. But the pain only seemed to spur the Doctor on, making a sound like a roar and wrapping his legs all the way around Jack's waist. 

The sudden hard press of the Doctor's heat against him sent shocks through his nipples and a jolt through his cock that ended with pre-cum moistening his underwear. Then he felt a tingling in the base of his spine that felt like the start of an orgasm, but as his pants tightened even more, he realized it was something else. His transformation was speeding up. He didn't stop the kiss, but his right hand moved down to struggle with the fastener on his pants-- he had wondered when he was going to grow the tail.

The realization that one of Jack's hands wasn't touching him anymore seemed to panic the Doctor, and he moved his lips more frantically against Jack's feline mouth, tightened the grip of his hand on Jack's shoulder blade and his legs on his waist. "Mmmnnn, ahhh... ahh--"

Jack's tail was growing longer and longer, making his clothes more and more uncomfortable-- it still felt like the base of his spine, but in a different place, and out of sync with the position of the rest of his limbs. His brain's model of the locations of his body parts could barely handle the discrepancy. 

And the infinitely erotic distraction of a Time Lord in heat, humping him while he tried to extricate himself from his pants-- it made it damn near impossible. Frustrated by claws and fur and paw pads, he finally gave up and slashed the fabric apart, over and over, until nothing was left but shreds of his pants and underpants, and scratches on his hips and thighs.

The sudden destructive frenzy shocked the Doctor into stillness. For a moment nothing could be heard but their combined heavy breathing, as the Time Lord realized that Jack's naked groin was now resting against his increasingly uncomfortable clothes.

Eyes shut tight, he untangled his arms and legs from Jack's body, as if letting go even for a second was painful. He lay back, resting himself on his elbows, and managed to open his eyes again, looking up at the captain who knelt between his legs.

Lying there, he looked more gorgeous than Jack could ever have imagined. Under sweaty and tousled hair, his eyes were wide, pupils expanded, brows tense. His teeth were showing as he panted and tried to catch his breath; his lips were swollen from arousal and all the too-rough kissing, a small cut in one spot from Jack's cat teeth. Inside his well-fitted shirt his chest moved irregularly. Small rips here and there in his clothing served as reminders of Jack's claws. There was a painful-looking bulge down his left thigh, his pant leg squeezed too tight around it-- Jack could see it pulsing, and... somehow undulating, too.

"Please," he breathed, each inhalation coming like a gasp. "Please, I need--" 

Jack could feel the Doctor's eyes on his feline shaft. He glanced down, and it looked even harder than it felt. He reached down and cupped it in the pads of his fingers.

The shape fit well in his hand, bulging in the middle and tapering thinner at the end. The little bumps all over the shaft were more sensitive than ever, and the way they massaged his paw pads felt amazing. Thank god he hadn't grown those spikes like a real cat. He moved his hand down lower, playing with the sheath, stroking the white fur on his balls.

"Please," the Doctor said again, louder this time, through teeth clenched tight together. 

"Yeah," Jack assured him, letting go of his own cock and bending down to stroke the inside of the Doctor's thigh. "I'm right here." He felt the muscles tense beneath his hand, heard a series of ragged "aa-AAH!" sounds as the Doctor tried to keep breathing. His hands fumbled with the fly of the Doctor's too-tight trousers, but once again the claws and paw pads confounded his efforts. "I-- I'm not used to using these yet," he stammered. "I'm sorry-- can I just rip the pants off?"

"Yes," said the Doctor, and it sounded like a growl, as he threw his head back and opened his legs wider.

Jack was trembling all over now, as he ran his hands gently down the Time Lord's thighs, claws extended just enough to break the fabric. The helpless bucking of hips beneath his touch didn't make things any easier, but he managed to tear a few long slits in the cloth with only minimal scratching of the Doctor's hypersensitized skin.

This was it. Holding his breath, he lifted away the remnants of the pants, exposing the Doctor's sex to light and air.

At first glance it didn't look much different from a human cock and balls. But as it started to respond to being freed from the too-tight clothes, Jack began to see that the shaft was actually four slender shafts-- fitted together like one, but beginning to unfurl, moving prehensilely like arms of an octopus.

Fascinated, he leaned close. They were flushed purple, like his own cock when it was painfully hard, and they gave off a clove-like scent tinged with musk. Very gently, he rested the pad of a finger against one. It was firm and smooth and slicked with some sort of natural lubricant. And very, very hot.

The Doctor clutched at the floor and clenched his teeth and moaned, and the tendril wrapped tight around Jack's finger, pulsing and contracting even once it was fully coiled. "Please, more..."

Jack stroked the curled tendril with the pad of his thumb. "I'm sorry, but-- but you're going to have to explain to me how these work." He could think of a lot of things to do with them, some of which made his erection jump and his breath catch in his throat just by thinking about them. But he had to know what the Doctor needed...

It took several moments and several rough breaths before the Doctor managed to speak. "They-- ahh, aaah-- they reach inside the female, a-aa-and wrap round her egg sac, and-- and it... oh, oh, OH! ...it absorbs the semen from them, by-- aaaAAAH yes, ah--" Just the touch of his finger and thumb was making the Time Lord's hips thrust upwards and his face gleam with sweat. Speech was gone as his eyes rolled up and his lips curled back in crazed desire.

"Okay, it's all right, you don't have to give me all the details," Jack murmured. "But-- well, okay, they can wrap around something..." He glanced down at his own nubbed erection, so hard that it was pressing against the fur of his belly. "Could they wrap around--"

"YES," groaned the Doctor, and now he was grabbing Jack by the waist and pulling him into his arms, in between his legs, their whole bodies touching, their shirts wrinkled between their chests and remnants of trouser legs tangled between their ankles. The Time Lord was panting and gasping as he clutched Jack against him, his breath hot against the delicate feline ear-- and now he was moaning uncontrollably, his hands gripping Jack's ass almost hard enough to bruise, because the slippery tendrils had found him, and all of them had wrapped around his bumpy shaft at once, tight and hot and wet, and each one stroking him with a different motion...

It was too much, an overload of pleasure. The warning tingle in the backs of Jack's thighs shot straight to his balls and cock in an instant. His tail thrashed from side to side. "Oh holy fuck, I'm going to--"

"No!" The Doctor looked up at him with panic on his face, and the tendrils tightened around him, tight enough that the discomfort just barely canceled out the pleasure enough to stave off climax. "Please, no! Not yet."

Jack took some deep breaths, trying to hold on, his ears folded tight against the fur of his head. "Okay," he said. "Okay, I can last a little bit longer. But not very long. F-fuck, it's just too good..."

The Doctor's teeth were bared in fear, his eyes pleading. "I need-- a lot more. A lot longer," he gasped. "Please, I need so much more, my god, it's killing me..."

And maybe it was-- maybe the Doctor's very survival depended on Jack's sexual stamina. Not since his teens had Captain Jack Harkness had any trouble lasting long enough to satisfy a lover. But he'd never had a lover who stimulated him like this... 

He breathed slowly, focusing on holding back the explosion building in his groin. His skin was on fire under his fur; all his muscles felt tight, a maddening tingling sensation running through him from his legs to his belly. How could he do this? Of course he could try using his hands or his mouth, or even his ass, if he failed-- but he wasn't sure any of those could give the Doctor what he needed. Judging from the response so far, his feline shaft was the perfect shape, size and texture to please those crazed tendrils.

Why did the Doctor need so much more? Why hadn't he climaxed already? He had certainly seemed horny enough to go off at the slightest touch. A sudden motion of the tendril-shafts made Jack breathe in sharply and dig his claws into the Doctor's back. Damn it, he knew nothing about Time Lord sexual physiology, nothing except the few words the Doctor had said to him...

"They reach inside the female and wrap round the egg sac." Of course! Inside the female. The Doctor needed the sensation of wrapping around something, but he also needed something wrapped around him at the same time.

The Doctor was losing control, starting to moan and growl again, his legs entwining with Jack's legs and his tentacles starting to move again, faster and faster. Jack bit his lip and tried to think fast, the pleasure driving him insane, his arms and thighs and even the tips of his ears trembling, his balls on fire with the need to release. Could he reach down and stroke the tentacles while they stroked him? Well, he could try, but he wasn't sure he could give them enough stimulation before he drove himself into his own orgasm. 

The Doctor was tossing his head from side to side again, his lips quivering, his mouth open and gasping helplessly. He looked as insane as Spock. Why the hell had he tried that telepathic stunt in the first place? 

And then Jack's eyes widened with inspiration, even as his thighs tingled harder in warning. The mind-meld!

It could work. Fighting the overwhelming urge to give in to pleasure, he slid his furred and padded hands off the Doctor's back, and reached back to where the tense fingers were gripping his backside. Gently, trying his best to be careful with his claws, he pulled the Doctor's hands loose. The Time Lord moaned in protest, but Jack clasped the hands tightly in his own, savoring their tense heat and the strength of their grip, moving them up to rest against the sides of his face.

And then, as the fingers seemed to realize where they were, instinct took over. With a groan from deep in his chest, the Doctor gripped Jack's face so hard it nearly hurt, hot fingers settling onto points on his temples and jawline, streaks of mental stimulation branching through his head like veins. The telepathic mind opened, madness thrusting into Jack's mind, probing into the centers of physical sensation and merging them with the Doctor's own. 

In an explosion of erotic telepathy, each man could feel everything the other felt. The cat-human could feel not only the prehensile shafts embracing him, but the feeling of having those shafts, the exquisite relief and fullness of wrapping them around a warm erection and contracting and stroking as hard as he could. The Time Lord felt not only the pleasure of holding Jack's cock in his grasp, but the pleasure that cock felt, wrapped in his own tendrils, shoving himself helplessly into hot tight wetness again and again. "Ahh! Ah-- oh yes, ah, ahh--"

It was a pleasure overload, making both arch their backs and hang onto each other for dear life, moaning and growling and bucking like mad. The double orgasm burned through both of them like a firestorm, electrifying their groins and shorting out their minds for a moment. "Fuck, ahh, oh my god yes!!"

And it went on and on. Even with the space between them flooded with semen, even as Jack's cock finally relaxed, the Time Lord's orgasm kept going, echoing through both their minds and making Jack groan along with him, as tingling pulses continued to reverberate through them.

God, the Doctor's face was gorgeous-- cheeks flushed, lips swollen and parted, teeth clenched and eyes tight shut as he rode out the waves of indescribable pleasure. And-- oh, holy fuck, what was happening?

His face was changing. Not slowly, the way Jack had changed, but fast-- the bared teeth sharpening, the bridge of the nose narrowing, the fur sprouting like a time-lapse video of grass. It was beautiful gray fur, shiny and sleek, and softer than anything Jack had ever touched. He grabbed the Time Lord by the hips and turned both of them onto their sides as the tail began to form, and the Doctor's back arched as the extending of his spine seemed to add to his ongoing climax. His eyes opened and they were bright blue-green, like a gemstone that didn't even exist, the slit-pupils dilated until they were almost round. 

Jack stroked the side of the Doctor's face and felt the ear changing, the tip of it stretching into a point. For just a second it looked like Spock's, and then it morphed into a more cone-like shape, thinner and more delicate, migrating higher up on his head. 

The caress set off the last convulsion of orgasm, the last wild dance of tendrils, stroking Jack's softening member like mad. They were still tendrils, the transformation hadn't changed that. But Jack could feel that they were taking on the texture of his own shaft, growing bumps that set off delicious aftershocks as they rubbed against his own. "Y-yes," the Time Lord gasped. "Aa-aahh, yes, Jim, yesss..." and the last wave of climax stiffened his whole body, made his new claws dig into Jack's shoulder blades before he finally relaxed.

They lay in the afterglow for long moments, becoming aware of reality, of the hard floor of the TARDIS. "Who the hell is Jim?" said Captain Jack, smiling and ruffling the fur on the Doctor's head.

The Doctor shrugged. "Damned if I know. That was from his mind, not mine."

He sounded like himself for the first time in a while, and Jack exhaled in relief. "So, are you feeling okay now? Not dying anymore?"

Then the Doctor seemed to become fully aware of his situation, looking down at their bodies-- lying together on the floor, legs still intertwined, shoes still on, though not fitting their digitigrade feet anymore. Trousers in shreds around their ankles. Shirts rumpled and clawed and semen-stained. The cluster of prehensile shafts, sticky and outspread between their bellies, one of them still wrapped loosely around Jack's cock.

Comprehension widened the blue-green eyes. "Oh, my god, did we just--"

Jack rested a hand on the Doctor's thigh. "Yeah, we did. We kind of had no choice."

The Doctor's ears folded down. "I--I remember now. I remember it all." He ran his clawed hands down his sides, feeling the sweaty fur. "And-- oh hell, I'm a cat now, aren't I?"

"Yeah. Sorry."

"So, what-- cat is a sexually transmitted disease now?" The Doctor pawed at his own head. "My god, cat ears."

Jack shrugged. "I guess it is. I'm sorry. If I had known, I... Well, I guess I would have done it anyway, because you were pretty much dying back there."

The feline Time Lord sighed, one hand on his face. Then he leaned back, his mouth opening and his ears folding back, as some wave of sensation overwhelmed him. The tendrils were coming back to life, the bumps on them swelling, their skin darkening to purple all at once. 

"And-- bloody hell, it's coming back now, isn't it?" he gasped.

Jack leaned in and kissed the Doctor between the neck and shoulder. "Don't worry. I'm right here."

All the Doctor could do was moan, as his hips rose up to meet Jack's, as his hands found their way to the human-cat's face and enveloped his mind in the madness once more. Jack was hard again, instantly, unbelievably, and rocking his hips in helpless abandon as the bumpy prehensile shafts wrapped and tightened and stroked. "Oh fuck yes..."

 

*****

To be continued


	3. Amok Time Lord: Chapter 3

**Summary for the Chapter:**

> The madness reaches its logical conclusion for the Doctor and Jack; meanwhile, Kirk and Spock experience their own complications.

Jim Kirk stood outside Spock's quarters for a few moments before buzzing the door. It stayed locked for a full ten seconds, but at last it slid open, and the captain moved inside.

"Spock?" he murmured, looking around. "I'm just checking in, Spock, just want to make sure you're all right--" and then he saw his first officer, sitting cross-legged on a corner of the bed. 

He was wearing his usual blue uniform shirt and black slacks, but something was different about him. The pointed ears were larger, their flesh thinner and more cupped, and they joined the head at a higher point than before. His fingers were steepled in meditation, and Jim could see that they had changed too, the tips sharpening into claws.

"Spock," he said again. "What's happened to you?"

And the Vulcan raised his head, turned to face him, the ears rising, his nose flared as if scenting a mate. 

Jim could see that the nose had narrowed and reshaped itself, and the once-dark eyes were a vivid yellow-green, glowing in the low light. It was still recognizable as Spock's face, but it was feral and insane. 

The Vulcan rose up and got off the bed, approaching him like a stalking panther. Kirk backed against the nearest wall. "Spock? What-- happened? You've... you've changed. This, this mating cycle you told me about-- is that a normal part of it?"

"I don't know," Spock answered, and it was definitely his voice, but with a tone of growl in it. "I don't know, because I am the last of my kind--" He paused, shook his head, seeming confused. "The-- the first, I mean. The first hybrid between humans and Vulcans. Nothing is normal for me."

Jim Kirk's eyes widened as Spock came closer. He was continuing to change as Jim watched, the jet-black hair spreading until it covered his face and neck, the mouth opening and teeth transforming before his eyes. 

"Spock, we're almost there," Jim said, pressing his back against the wall. "Just a few days' travel. We're taking you home. You can relax now. You'll get what you need, soon."

Spock turned back for a second, growling and pulling at the waistband of his own pants, managing to lower them enough to free the tail that was growing from the base of his spine. It was slender, graceful, covered in silky black fur. 

Jim's eyes couldn't help wandering to the rest of the cat-Vulcan's lower body-- the lean hips, the bare feet that were shape-shifting until the heels were thin and almost halfway up the calf. Claws formed on the toes that now supported his weight, and the black fur was spreading to them too, and to his hands. It had covered his face all over by now, longer on the head and cheeks, short and fine on the brow and the bridge of the nose.

And in the center of Jim's vision, straining inside the uniform pant leg, was an erection that took the captain's breath away. The fabric imprisoned it so tightly that he could see its texture-- not just the Vulcan double ridge he'd heard rumors of, but feline bumps all over. It was swollen so thick and full that it looked excruciatingly painful, a moist spot already at the tip of it. 

Jim felt his face flush with arousal, his own member beginning to swell. He was probably one of the most sexual beings in the galaxy, experienced with partners both male and female, as well as some other sexes found only in space. He'd had fantasies about half the crewmembers on his ship, including Spock-- with the Vulcan's looks, how couldn't he? And the friendship between them was already so deep, their concern for each other so nearly obsessive, that Jim had often thought the act of sex was all it would take to make them lovers in every sense... 

But fantasizing was different from acting on fantasies. And he'd certainly never imagined that his emotionally controlled first officer would have any interest in screwing him. That sure was what it looked like right now, though, as Spock came close enough for Jim to feel the fevered heat of his body.

"What I need is you," he said, in the Vulcan's unmistakable deep and throaty voice, but with animal undertones-- and he pressed that lean body against every centimeter of Jim's, all at once. 

Jim let out a hard, unsteady breath at the sudden contact. His pelvis rocked forward involuntarily, and his hands found Spock's hips and held them, not sure whether to push him away or draw him closer. 

"You said you had to go home to take a mate," he reminded Spock, trying not to breathe too fast. "That must mean there's someone on Vulcan, waiting for you. Isn't there?"

Spock's face was up against Kirk's, now, his breath hot. "I don't want her," he growled. 

And his clawed hands were reaching behind Jim and grabbing his ass, pulling them together so tightly that the contact of their erections was an explosion of pleasure.

Jim's control gave out, and he made an animalistic noise of his own, giving up and just letting his body do what it wanted. He let himself thrust against Spock, let their painfully swollen members slide together through the clothes and ooze pre-cum into their undershorts, let his hands grip the cat-Vulcan's ass and rub the base of the tail as he pulled him in to grind harder.

Spock made a sound that embodied the essence of sex, a moan that was half the familiar smooth-rough Vulcan voice and half the cry of a cat in heat. His motions got faster, and his face pinned Jim's head against the wall, opening his feline muzzle against the human's lips. The urgency and pressure of the kiss made Jim dizzy-- it scraped him with sharp teeth and rasp-like tongue, but it filled him with nothing but the urge to respond, to kiss back and push his tongue over the sharpness and roughness again and again, to open himself to pain that was as exquisite as the pleasure.

At Jim's response, Spock inhaled and moaned at once, and his shaft leapt inside his clothes. "I want," he growled, "I need-- now--"

Jim needed no more encouragement. He moved his hands up and down the Vulcan-cat's back a few times, and began to lower himself to his knees, stroking Spock sensually as he moved, caressing his shoulder blades and the small of his back, and finally his buttocks and tail again. As he moved lower, he mouthed Spock's flesh through his shirt, finding a nipple, the edge of a rib, the base of his navel, and leaving wet marks on the blue fabric as he kissed them. 

The cat-Vulcan's breathing went crazy, inhalations and exhalations trying to happen out of order, his tail thrashing and his legs suddenly seeming so weak he was about to fall over. Jim gripped Spock's behind as tightly as he could, to support him, and helped him turn until he was the one with his back against the wall. 

"Relax," he murmured against the bulge in his first officer's pants. 

Spock took some unsteady breaths and rested his hands against the wall, claws already digging into the hard polymer. "Please-- now--" He sounded as if he was in agony.

Jim Kirk's hands were shaking, but he managed to unfasten the pants and push them down just far enough for Spock's maddened hardness to break free. The captain's knees were on the floor now, his face up against the Vulcan's groin, and just the air-motion of his breath was making the hard cock jump and leak drops of pre-cum.

It was magnificent, as long as Jim's own, and almost twice as thick-- flushed copper-green with Spock's alien blood. It glistened with the semen drops it had already shed, and Jim could see the Vulcan's pulse in the little swollen cat bumps all over the shaft, and the two elegant ridges that crowned the tip. There was a furred sheath around the base, like an animal's, probably part of the cat-transformation, and the balls were covered in fur as well. Jim reached up and cupped them in his hand, pressing his lips against the blue-green cock head.

Spock jerked his head back against the wall, roaring and groaning and shoving his pelvis against Kirk's face so hard that the captain's lips were nearly bruised against the hardness of the shaft. The human gave a few rough breaths and put both hands on Spock's hips, moving them in stroking motions as he lowered his mouth to the head of the alien erection again.

He opened his lips over its crown, taking a few centimeters fully into his mouth, sliding his tongue up and down against the underside. 

"Ahh! AAaa-AHH!" Spock's chest heaved inside his uniform, and his feet moved and clawed against the floor, shifting his legs wider apart as he bucked into Jim's oral caress. "Y-yes, more-- more--"

Jim opened his mouth wider, taking in more, tightening his lips around the fevered cock and moving the tip of his tongue across its surface. It was an unbelievably erotic feeling, sending shocks of pleasure into Jim's own hard-on, making it tingle and spurt a tiny bit of pre-cum with no more stimulation than his hips' slight motion inside his pants. 

The taste was musky and coppery, the feel was the perfect mix of soft skin over hardness, stroking the inside of his mouth with its complex texture. He explored what each touch did to the cat-Vulcan-- the hard thrust and series of too-fast panting breaths, when he touched his tongue to one of the feline nubs; the throat-deep moan and the arched back, when he licked in between the Vulcan ridges. 

Then the pon farr went past some threshold of madness, and there was no more chance to be meticulous with his touches-- Spock was moving too fast, too uncontrollably, roaring and thrashing his tail and fucking Jim's mouth with all the frenzy of the blood fever. It was all Jim could do just to keep his mouth wide open and his teeth off Spock's member, to let Spock take what he so desperately needed. 

And god, it was such a turn-on, all the same-- Spock, the unattainable, unapproachable, unexpressive Vulcan, gone sexually insane, turned into a rutting beast. Jim throbbed against the fly of his pants, but his hands kept up their sensual massage of Spock's hips and ass, letting the pain of his trapped erection be a delicious feeling in itself.

Then, all at once, Spock let loose a sound like a snarl and a scream, and his hands gave one last scrape at the clawed-up wall and then moved down to seize Jim's face. 

The paw-pads pressed hard on his cheekbones; the fingers settled themselves onto the pressure points of a mind-meld, with a spot of pain on each one where the claw dug in. He was holding Jim's face tightly against the jerking and thrusting of his hips, but he was also penetrating his mind, pouring into his head until their thoughts and emotions and sensations were one boiling pool of pleasure. 

Jim moaned around the shaft. He was Kirk and Spock at the same time; his own cock strained in his pants, but, superimposed on that feeling, he was a bumped and ridged Vulcan-cat in heat, thrusting into warm wetness. He was a human, aroused beyond reason by his sexy first officer, but he was also a Vulcan in the throes of pon farr, all thought reduced to the searing agony of his need and the breathtaking relief of the touches that eased it.

He was both of them, both sides of the need and the pleasure. Both cocks jerked and spilled violently at the same time, both sets of lungs struggled to breathe through roar-growls of ecstasy, as both minds shattered in the supernova of their release.

They came back to reality, Spock trembling against the wall, Jim shaking on his knees and wiping the corner of his mouth. They just barely managed to lower themselves into an embrace on the floor. Spock's leg ended up between Kirk's thighs, where it triggered aftershocks as it made him rub against the slippery stain in his pants.

"Aaahh," Jim gasped. "Ah, ahh--" Slowly, the aftershocks faded and his moans quieted to short hard breaths. "Ah. W-Wow."

He looked at Spock, still panting as he lay on his side. The Vulcan's fur shone with sweat, his tail twitched. His belly was slick with semen that had gotten past Jim's efforts to swallow... but his cock was, impossibly, still as hard as when they had begun.

"Are you okay?" Jim rubbed Spock's furred chest through the uniform shirt. "Spock? Did that... help at all? You're still--"

Spock turned his head to the side and breathed out raggedly. "You can't-- satisfy it," he said. "I still-- have to go home. The mate my family ch-chose for me... there is a tele-- telepathic link. It can't break, it can't stop, not until I-- meet her face to face." His eyes clenched shut.

"And then what?" Jim was shocked to realize that jealousy was tinging his concern. "Will you have to fuck her? Will you have to get married to her? Isn't there any way either of you can say no?"

"I-- I don't know," Spock said. "I t-told you before-- nothing is normal for me. I d-don't know what will happen. I-- I want you. I don't want anyone else. But I don't know-- what I can do to stop it." He finally managed to open his eyes, the gold-green pools of light giving Kirk a concerned look. "Jim? Are y-you all right?"

Captain Kirk looked down at his own body. His feet and calves did feel strange-- not just cramped from the position he was in, but-- 

He moved his legs. The uniform boots, usually so hard to pull off, slipped from his feet immediately. 

His heart kicked into a faster pace. The bones between his toes and heels had stretched; his heels had climbed up several centimeters; his toenails were growing into claws that were ripping through his socks. 

He grabbed his right leg in both hands, but was distracted by the hands themselves, the calluses of his fingers and thumbs swelling into pads, the nails narrowing and lengthening. Orange tabby fur was sprouting all over, making his skin itch inside his clothes. His mouth didn't even seem to open the same way. He stuck out his tongue, and felt it scrape his upper lip like sandpaper; felt his teeth prick it like needles.

"Omigod." He pulled his pants down just in time for his backbone to extend past his ass until it became a tail, thrashing back and forth with a mind of its own. He turned himself onto his back and opened his thighs, letting his new tail stretch out on the floor between his legs. In front, meanwhile, his--

It must be something about this transformation. Or was it the aftereffects of the mind-meld? Even though he'd had a nuclear explosion of an orgasm just a few minutes ago, his cock was swelling again, his balls were tightening, and his whole groin was hypersensitized to the changes that were taking place there. The skin at the base of his shaft folded into a sheath, and white fur began to spread across that and his ball sac, tickling the tender flesh. His erection swelled thick in the middle and narrowed at the tip, and extra-sensitive bumps started forming all over it, rising to the skin like bubbles. 

Spock was watching him with a look in his eyes like starvation. As the Vulcan-cat saw his flesh spring to hardness, saw it become feline, his tongue ran over his teeth and lips, and the black panther body rose to move closer to him, to position itself above him, as he rested on his back on the floor. 

"Spock," Jim whispered. "Did you do this to me?"

The cat-Vulcan nuzzled the side of his face. "I d-don't know."

"If we keep fucking, will we change back?" Jim moaned as Spock's muzzle brushed his ear.

Spock's eyes narrowed. "I don't know."

"Will more sex help at all? Are you going to get any relief from this, to last you until you get home?" Jim couldn't help raising his hips up to meet Spock's, trying to collide their cocks together.

"I don't know." Spock licked his neck, then bit it, and the mix of pain and pleasure made his balls tighten and his cock jump.

"But-- if we're going to be waiting a few days anyway--" Jim Kirk grabbed Spock's waist in his hands, letting his claws rip the hem of the uniform shirt. "Then we might as well enjoy it..."

Spock lowered his body onto Kirk's, their erections lying against each other from base to tip, a sudden jolt of pressure and sensation. Spock growled again, but this time it was more like a purr. 

"Yes."

 

*****

 

The last of the Time Lords was on fire.

His fur was tangled and sweaty and sticky. His back hurt from arching. His hips ached from thrusting. His balls burned with the need for release. Even his tail was exhausted from thrashing back and forth.

For the fifth time, his prehensile shafts had come back to pulsing, twisting life, and once again Captain Jack Harkness knelt between his wide-open thighs, watching the tendrils with fascination, preparing to give himself to them.

The Time Lord's mind was too clouded with lust for any clear thought, but somewhere in with all the arousal was a warm burn of gratitude. Jack had been infinitely kind to him throughout this ordeal, responding to every urge, touching him exactly where he needed, gently or roughly depending on the Doctor's cravings. And when memories of all those moments flashed up in the fevered mind, his sexual response was tempered with a thankfulness that felt almost like love.

And then his head tossed back and his hips jolted upwards, because Jack was leaning down further, lowering himself to lie almost fully prone on the floor... pressing his mouth to one of the shafts that undulated between the spread legs.

"Aa-aa-aahh!" The Doctor's claws scraped the floor. The heat and moisture of the half-opened lips drove him wild, he needed more, needed--

The lips opened wider, still holding back just enough to keep the teeth away, and now the rough cat tongue was caressing him, wet and warm, dragging against the tingling sensitivity of the feline bumps on his tendrils. "OHH! Y-yes, YES, aahhh..." 

Jack kept licking, up and down the tendril, then nuzzling the crevice between the bases of the prehensile shafts before beginning to lick down another one. The Doctor was beyond control, his pelvis thrusting frenetically, moans breaking free from his throat every second, his lungs and throat too full of frenzied breath to form another real word, even "please" or "more."

The stroking of the tongue continued, leaving the bumps more swollen and the flesh moving more wildly in its wake. Finally, after eons of wonderful torture, every centimeter of all four shafts was glistening with moisture from Jack's tongue. And the Doctor couldn't breathe, could barely keep both his hearts beating, needed more, needed it with every trace of energy in his body and mind...

And then it was there-- Jack's body in his arms, chest against chest, legs entwined with legs, mouth on mouth, and the glorious swelling of Jack's cock pressing into his groin, welcoming the frantic embrace of need.

The tendrils wrapped and stroked and went insane with motion, and in the bucking madness the Time Lord's hands left the claw-marked floor to grip Jack's face, open their minds together once more, let the climax rip through them all at once and tear them to pieces.

 

*****

 

The mind-meld ended bit by bit, leaving Jack still gasping on top of the Doctor's body. That one had felt the most intense of all, as if it might have finally satisfied the need. God, that amazing clove-musk taste-- he licked his lips; it was still there on his tongue.

He rolled onto his side, looking over at the Doctor, who seemed relaxed for the first time in hours-- his eyes were closed but not clenched, his feline ears were at rest instead of twitching. Then he gave a soft breath, seeming to wake up.

There was that moment of confusion again, as the madness faded, as the Doctor blinked his eyes at reality. "Did you and I just--" 

And then, once more, the moment of realization, looking down at the entangled genitals, the sweat-and-semen-soaked fur. "Oh, bugger."

"Sure, if you like-- but you'll have to give me some time to recover." Jack leaned back and grinned, running a hand through the fur on the side of his own face.

The Doctor got to his feet, seizing up the last remnants of his clothes to cover himself. "I'm-- I'm fine. I'm finished. I don't need anything more." Jack thought he could see him blushing furiously, even through the fur. "And you're shedding."

"What?"

"You're shedding cat hair, all over my TARDIS." The Doctor rubbed his forehead, and a shower of fine gray fur sprinkled past his eyes. "Oh, bloody hell, so am I."

Jack looked at the backs of his hands. The claws were shortening and broadening, beginning to look like fingernails again. When he rubbed his hands together, the fur fell out with no resistance, leaving patches of human skin.

"We're changing back, aren't we?" Jack murmured. He felt his ears. They were thickening, moving back downwards, the points receding.

"Apparently so." The Doctor licked his teeth, seeming relieved that they were no longer so sharp, and that his tongue was growing thicker and smoother. "Whatever your Caitian friend injected you with, to change your appearance-- it seems it couldn't hold up, to such a-- prolonged and intense rush of-- hormones." Jack was certain he could see the blush now. 

"Well." Jack looked down at his legs, watching the high-up heels move downward and become thick enough to form the bottoms of human feet. The Doctor's demeanor was still confusing him, but they were both alive, both back to their old selves, and that was all that mattered.

"Oh, they will perfect the formula someday," the Time Lord went on. "Those scientists M'Rai was influencing-- their work does make it into the future. I've seen it." His attention suddenly shifted back to his naked and sticky body, and embarrassment replaced his momentary history-lecture mode. Fur fell off his limbs as he tried to move them into the optimum position for covering his nudity. "Anyway--" He paused as if struggling with the words. "Thanks."

Jack tilted his head. "Just 'thanks'?" He wasn't sure if he had been expecting declarations of love, but this seemed anticlimactic.

"Yes, thanks. That's what I'm supposed to say, isn't it? I'm still not sure exactly what just happened, but it looks as if you saved my life, so-- thanks." 

Clutching the fragments of clothing around him, he started walking toward the stairs, his gait changing from tiptoe to plantigrade as he moved. "And now I'm going to go get cleaned up and dressed, and we're going to go find that rift in space M'Rai tore to send us here, before he finds us. Then we're going to go back to our own universe, and seal the rift permanently behind us, if at all possible. And then I'll drop you off wherever you like."

The Doctor vanished into the upper regions of the TARDIS, and Jack sat alone, watching fur fall off his arms and chest. 

He wished that, at the very least, he could say "thanks" too, for the most incredible and wonderful sexual experience he'd ever had. But it would sound so wrong, thanking the Doctor for something he'd had no control over; rubbing his face in the fact that Jack had enjoyed it. 

The Doctor had clearly enjoyed it too, more than Jack had ever seen anyone enjoy anything-- but now that the madness had worn off, he was embarrassed about it, wanting to pretend it hadn't happened. And... that was his prerogative. Jack couldn't make him want something he didn't. 

He sat still, feeling his tail shrink back into his spine, feeling the bumps recede on his shaft. He would never be able to forget this. For himself, Jack Harkness couldn't pretend it hadn't happened, even if he wanted to. It would be with him for the rest of his long, long life.

 

*****

 

The Doctor started a very hot shower, and stood under it, letting the water sluice his cat fur off and down the drain. His hearts beat hard and fast every time a memory surfaced from those hours of insanity. 

He was utterly satisfied, the madness was cured, he didn't need any more-- but that didn't stop the memories from touching him somewhere deep and tender, awakening the feelings he had tried so hard to shield himself from.

He was a Time Lord. He couldn't love a human-- they grew old and died and broke his hearts. Except Jack. Jack was the only human who could be a true partner for him, live out a life as long as his. 

But-- 

The Doctor sighed, scrubbing at his shoulders, feeling the fur wash off like soap lather. It was too late. There was the prophecy of the four knocks, coming up too fast in his future. 

Not very long from now, he would be gone forever, or else regenerated, changed into someone who might or might not have any feelings for the captain. To show any sign of love right now would be cruel, giving Jack a taste of something he might soon lose forever.

So he would have to drop Jack off on some nice planet, maybe try to fix him up with someone who could love him in a human way-- give him some years of normal happiness. Maybe someday, if the Doctor's future regeneration hadn't lost all traces of what he was feeling right now, they would meet again in happier circumstances. 

But for now, it would have to be nothing more than "thanks" and "goodbye." His eyes stung, but if there were tears, they were lost in the spray of water.

 

*****

 

"Come on, Spock, let's go mind the store." 

Captain Kirk and his first officer left sickbay, entering the corridor with a frisson of self-consciousness, a sudden awareness of being alone together. 

It was finally all over, the trip to Vulcan, the duel, McCoy's clever intervention. But was it truly finished?

Kirk looked at Spock with concern. "Are you all right?" he asked. "Is the-- madness really gone?"

"Of course." The Vulcan raised an eyebrow. "I said so, did I not?"

"I know." Kirk looked down. "It's just-- it doesn't seem to make sense. You went mad enough to fight for your mate. Then, when you won, you suddenly had no interest in-- mating with her. I don't see how that works, biologically. Is it just some... some glitch, because you're half human?"

"Perhaps." Spock looked thoughtful. "It feels... What it feels like..." The word sounded strange from the Vulcan lips. "I know this is impossible. But it feels as if someone else mind-melded with me, and took away part of the blood fever-- experienced part of it for me, so that I would not have to suffer it all." 

He lowered his eyebrows in thought. "There is a strange memory-- probably a hallucination I experienced in my quarters, while I was going more and more insane--"

Jim Kirk looked at him, the human eyes intense. "Do you mean-- what happened between you and me? Spock, you didn't hallucinate that. That was real." The captain took Spock's hand, their fingers entwining. 

Spock blushed, green blood climbing his face like verdigris. "I was thinking of a different memory, one that probably was a hallucination," he said. "But I--" His voice cracked. "I am-- glad that part was real." 

Kirk squeezed his hand. "That was probably me, taking away part of your madness. We mind-melded, didn't we? And I... I certainly felt as if I was in pon farr too, for a while there."

Spock inclined his head. "Yes... that may have been it." 

The two of them walked side by side, in silence, for a few moments. "And-- the part when our bodies-- transformed, for a while-- was that real too?" Spock asked.

Kirk chuckled. "Yes, strangely enough, it was. And I still have no idea why. But I've seen so many strange things in this universe-- sometimes I just have to pick and choose which ones to ask questions about."

He let go of Spock's hand, trailing his fingers up the Vulcan's arm, his neck, finally touching his ear. "And besides," Kirk added, reveling in the Vulcan's gasp and blush at the caress, "--you were pretty damn sexy as a cat."


End file.
